Memory Management. Reading: Silberschatz chapter 9 Reading: Stallings. chapter 7 EEL 602
|
|
- Franklin Pearson
- 7 years ago
- Views:
Transcription
1 Memory Management Reading: Silberschatz chapter 9 Reading: Stallings chapter 7 1
2 Outline Background Issues in Memory Management Logical Vs Physical address, MMU Dynamic Loading Memory Partitioning Placement Algorithms Dynamic Partitioning Buddy System Paging Memory Segmentation Example Intel Pentium 2
3 Background Main memory fast, relatively high cost, volatile Secondary memory large capacity, slower, cheaper than main memory and is usually non volatile The CPU fetches instructions/data of a program from memory; therefore, the program/data must reside in the main (RAM and ROM) memory Multiprogramming systems main memory must be subdivided to accommodate several processes This subdivision is carried out dynamically by OS and known as memory management 3
4 Issues in Memory Management Relocation: Swapping of active process in and out of main memory to maximize CPU utilization Process may not be placed back in same main memory region! Ability to relocate the process to different area of memory Protection: Protection against unwanted interference by another process Must be ensured by processor (hardware) rather than OS Sharing: Flexibility to allow several process to access the same portions of the main memory Efficiency: Memory must be fairly allocated for high processor utilization, Systematic flow of information between main and secondary memory 4
5 Binding of Instructions and Data to Memory Compiler Generates Object Code Linker Combines the Object code into a single self sufficient executable code Loading Copies executable code into memory Execution dynamic memory allocation 5
6 Binding of Instructions and Data to Memory Address binding of instructions and data to memory addresses can happen at three different stages Compile time: If memory location known a priori, absolute code can be generated; must recompile code if starting location changes Load time: Must generate relocatable code if memory location is not known at compile time Execution time: Binding delayed until run time if the process can be moved during its execution from one memory segment to another most general purpose OS 6
7 Logical Vs Physical Address Space Each logical address is bound to physical address space; Logical address generated by the CPU; also referred to as virtual address Physical address address seen by the memory unit Logical and physical addresses ; Identical in compile-time and load-time addressbinding schemes Differ in execution-time address-binding scheme Logical address Virtual address 7
8 Memory-Management Unit (MMU) The runtime mapping from virtual physical address Relocation register is added to every address generated by user process The user program logical addresses, it never sees the real physical addresses 8
9 Dynamic Loading Routine is not loaded until it is called Better memory-space utilization unused routine is never loaded Useful to handle infrequently occurring cases, e.g. error handling routines No special support from the OS required implemented through user program design 9
10 Memory Partitioning Two schemes used in several variations of now-obsolete OS Fixed Partitioning: OS occupies fixed portion of main memory, rest available for multiple processes. Two alternatives; Equal size fixed partitions any process partition size can be loaded Unequal size partitions several unequal size partitions, process of matching sizes Problems with equal size fixed partitions: If program is bigger than a partition size, use of overlays Main memory utilization is extremely inefficient; Internal Fragmentation waste of space internal to partition due to the fact that block of data loaded is smaller than partition 10
11 Unequal-Size Partitions Assign each processes the smallest partition to which it will fit Advantages: Process are always assigned in such a way as to minimize wasted memory within a partition internal fragmentation Relatively simple and require minimal OS software and overhead Disadvantages: Limitations on the active number of processes, number of partitions specified at system generation time Small jobs cannot utilize partition space efficiently; In most cases it is an inefficient technique 11
12 Placement Algorithm with Partitions Equal-size partitions Because all partitions are of equal size, it does not matter which partition is used Unequal-size partitions Can assign each process to the smallest partition within which it will fit Queue for each partition size Processes are assigned in such a way as to minimize wasted memory within a partition 12
13 Placement Algorithm with Partitions 13
14 Dynamic Partitioning Developed to address the drawbacks of fixed partitioning Partitions of variable length and number; Process in bought into main memory, it is allocated exactly as much memory as it requires Leaves Holes First at the end eventually lot of small holes Memory becomes more fragmented with time, memory utilization External Fragmentation Memory that is external to all partitions becomes increasingly fragmented Compaction Used to overcome external fragmentation OS shifts processes so that free memory is together in one block Compaction requires use of dynamic relocation capability Time consuming procedure and wasteful of processor time 14
15 Dynamic Partitioning 15
16 Placement Algorithms Compaction is time consuming OS must be clever in plugging holes while assigning processes to memory Three placement algorithms Selecting among free blocks of main memory Best-Fit: Closest in size to the request First-Fit: Scans the main memory from the beginning and first available block that is large enough Next-Fit: Scans the memory from the location of last placement and chooses next available block that is large enough 16
17 Placement Algorithms - Example Allocation of 16 MB block using three placement algorithms 17
18 Placement Algorithms Which of the above approaches is the best? Process Size/Sequence, General Comments First-Fit Simplest, usually the best and fastest Next-Fit Slightly worst results with next fit Compaction may be more frequently required Best-Fit Usually the worst performer; main memory is quickly littered by blocks too small to satisfy memory allocation requests Compaction - more frequently than other algorithms 18
19 Buddy System Drawbacks Fixed partitioning: Limits number of active process, inefficient if poor match between partition and process sizes Dynamic Partitioning: Complex to maintain, includes the overhead of compaction Compromise may be the Buddy System - Entire space available is treated as a single block of 2 U If a request of size s such that 2 U-1 < s 2 U, entire block is allocated Otherwise block is split into two equal buddies Process continues until smallest block greater than or equal to s is generated 19
20 Buddy System - Example Initial block size 1 MB; First request A is for 100 KB 20
21 Buddy System - Example Binary tree representation immediately after Release B request. 21
22 Relocation A process may occupy different partitions which means different absolute memory locations during execution (from swapping) Compaction will also cause a program to occupy a different partition which means different absolute memory locations 22
23 Paging Partitioning main memory small equal fixed-size chunks Each process is divided into the same size chunks pages Chunks of memory frames or page frames Advantages No external fragmentation Internal fragmentation only a fraction of last page of a process OS maintains a page table for each process Contains frame location for each page in the process Memory address a page number, a offset within the page Processor hardware logical-to-physical address translation 23
24 Paging - Example Assignment of process pages to free frames 24
25 Paging - Example Assignment of process pages to free frames. 25
26 Paging - Example Data structures for page tables at time epoch (f) 26
27 Paging - Example Convenience in Paging scheme Frame size power of 2 Relative address (wrt origin of program) and the logical address (page # and offset) are same Example - 16 bit address, page size 1K or 1024 bytes Maximum 64 (2 6 ) pages of 1K bytes each Advantages Logical addressing transparent to programmer, assembler, linker Relatively easy to implement a function to perform dynamic address translation at run time 27
28 Paging - Example 28
29 Paging - Example Logical-to-physical address translation in Paging 29
30 Paging - Example Logical-to-physical address translation in Paging 30
31 Implementation of Page Table Different methods of storing page tables, OS dependent Pointer to page table PCB Hardware implementation of page tables Page table Set of dedicated high speed registers, Simplest Suitable for small page table sizes, Usually very large requirements Page table is kept in main memory Page-table base register (PTBR) points to the page table Two memory access, page table and other for data/instruction Memory access slowed by a factor of two Solution to the two memory access problem Usage of a special fast-lookup hardware cache called associative memory or translation look-aside buffers (TLBs) TLB contains Page # Frame #, Small # of TLB entries ( ) 31
32 Paging Hardware With TLB 32
33 Shared Pages Shared code One copy of read-only (reentrant) code shared among processes, e.g. text editors, compilers Shared code must appear in same location in the logical address space of all processes Private code and data Each process keeps a separate copy of the code and data The pages for the private code and data can appear anywhere in the logical address space 33
34 Shared Pages Example Sharing of code in paging environment 34
35 Segmentation Memory-management scheme that supports user view of memory Program Collection of segments (name and length) Complier automatically constructs segments reflecting input program Example A C complier might create separate segments for the following main program, procedure, function, object, local variables, global variables, common block, stack, symbol table, arrays 35
36 Segmentation The program/process and its associated data is divided into a number of segments All segments of all programs do not have to be of the same length There is a maximum segment length Addressing consist of two parts - a segment number and an offset Since segments are not equal, segmentation is similar to dynamic partitioning 36
37 Address Translation Architecture 37
38 User s View of a Program 38
39 Logical View of Segmentation user space physical memory space 39
40 Example of Segmentation 40
41 Sharing of Segments 41
42 Segmentation Compared to dynamic partition, segmentation program may occupy more than one partition and these partitions need not be contiguous Segmentation eliminates the need for internal fragmentation but like dynamic partitioning it suffers from external fragmentation Process is broken in small pieces, the external fragmentation is less with segmentation than dynamic partition Paging is invisible to the programmer, segmentation is usually visible 42
43 Segmentation EXAMPLE: Logical Addresses. 43
44 Segmentation EXAMPLE: Logical-to-physical address translation in Segmentation 44
45 Hierarchical Page Tables Most systems support a large logical address space , page table itself becomes excessively large Break up the logical address space into multiple page tables A simple technique is a two-level page table 45
46 Two-Level Paging Example A logical address (32-bit machine with 4K page size) is divided into: a page number consisting of 20 bits a page offset consisting of 12 bits Since the page table is paged, page number is further divided into: a 10-bit page number a 10-bit page offset Thus, a logical address is as follows: page number page offset p i p 2 d where p i is an index into the outer page table, and p 2 is the displacement within the page of the outer page table 46
47 Two-Level Page-Table Scheme 47
48 Address-Translation Scheme Address-translation scheme for a two-level 32-bit paging architecture 48
Memory Management Outline. Background Swapping Contiguous Memory Allocation Paging Segmentation Segmented Paging
Memory Management Outline Background Swapping Contiguous Memory Allocation Paging Segmentation Segmented Paging 1 Background Memory is a large array of bytes memory and registers are only storage CPU can
More informationChapter 7 Memory Management
Operating Systems: Internals and Design Principles Chapter 7 Memory Management Eighth Edition William Stallings Frame Page Segment A fixed-length block of main memory. A fixed-length block of data that
More informationChapter 7 Memory Management
Operating Systems: Internals and Design Principles, 6/E William Stallings Chapter 7 Memory Management Patricia Roy Manatee Community College, Venice, FL 2008, Prentice Hall Memory Management Subdividing
More informationMemory management basics (1) Requirements (1) Objectives. Operating Systems Part of E1.9 - Principles of Computers and Software Engineering
Memory management basics (1) Requirements (1) Operating Systems Part of E1.9 - Principles of Computers and Software Engineering Lecture 7: Memory Management I Memory management intends to satisfy the following
More informationOPERATING SYSTEM - MEMORY MANAGEMENT
OPERATING SYSTEM - MEMORY MANAGEMENT http://www.tutorialspoint.com/operating_system/os_memory_management.htm Copyright tutorialspoint.com Memory management is the functionality of an operating system which
More informationThe Deadlock Problem. Deadlocks. Deadlocks. Bridge Crossing Example
The Deadlock Problem Deadlocks A set of blocked processes each holding a resource and waiting to acquire a resource held by another process in the set. Example System has 2 tape drives. P 1 and P 2 each
More informationOperating Systems, 6 th ed. Test Bank Chapter 7
True / False Questions: Chapter 7 Memory Management 1. T / F In a multiprogramming system, main memory is divided into multiple sections: one for the operating system (resident monitor, kernel) and one
More informationOPERATING SYSTEMS MEMORY MANAGEMENT
OPERATING SYSTEMS MEMORY MANAGEMENT Jerry Breecher 8: Memory Management 1 OPERATING SYSTEM Memory Management What Is In This Chapter? Just as processes share the CPU, they also share physical memory. This
More informationMemory unit sees only the addresses, and not how they are generated (instruction counter, indexing, direct)
Memory Management 55 Memory Management Multitasking without memory management is like having a party in a closet. Charles Petzold. Programming Windows 3.1 Programs expand to fill the memory that holds
More information& Data Processing 2. Exercise 3: Memory Management. Dipl.-Ing. Bogdan Marin. Universität Duisburg-Essen
Folie a: Name & Data Processing 2 3: Memory Management Dipl.-Ing. Bogdan Marin Fakultät für Ingenieurwissenschaften Abteilung Elektro-und Informationstechnik -Technische Informatik- Objectives Memory Management
More informationW4118: segmentation and paging. Instructor: Junfeng Yang
W4118: segmentation and paging Instructor: Junfeng Yang Outline Memory management goals Segmentation Paging TLB 1 Uni- v.s. multi-programming Simple uniprogramming with a single segment per process Uniprogramming
More informationMemory Allocation. Static Allocation. Dynamic Allocation. Memory Management. Dynamic Allocation. Dynamic Storage Allocation
Dynamic Storage Allocation CS 44 Operating Systems Fall 5 Presented By Vibha Prasad Memory Allocation Static Allocation (fixed in size) Sometimes we create data structures that are fixed and don t need
More informationMemory Management 1. Memory Management. Multitasking without memory management is like having a party in a closet.
Memory Management 1 Memory Management Multitasking without memory management is like having a party in a closet. Charles Petzold. Programming Windows 3.1 Programs expand to fill the memory that holds them.
More informationVirtual vs Physical Addresses
Virtual vs Physical Addresses Physical addresses refer to hardware addresses of physical memory. Virtual addresses refer to the virtual store viewed by the process. virtual addresses might be the same
More informationTechnical Properties. Mobile Operating Systems. Overview Concepts of Mobile. Functions Processes. Lecture 11. Memory Management.
Overview Concepts of Mobile Operating Systems Lecture 11 Concepts of Mobile Operating Systems Mobile Business I (WS 2007/08) Prof Dr Kai Rannenberg Chair of Mobile Business and Multilateral Security Johann
More informationCS5460: Operating Systems
CS5460: Operating Systems Lecture 13: Memory Management (Chapter 8) Where are we? Basic OS structure, HW/SW interface, interrupts, scheduling Concurrency Memory management Storage management Other topics
More informationChapter 12. Paging an Virtual Memory Systems
Chapter 12 Paging an Virtual Memory Systems Paging & Virtual Memory Virtual Memory - giving the illusion of more physical memory than there really is (via demand paging) Pure Paging - The total program
More informationTwo Parts. Filesystem Interface. Filesystem design. Interface the user sees. Implementing the interface
File Management Two Parts Filesystem Interface Interface the user sees Organization of the files as seen by the user Operations defined on files Properties that can be read/modified Filesystem design Implementing
More informationOperating Systems. Virtual Memory
Operating Systems Virtual Memory Virtual Memory Topics. Memory Hierarchy. Why Virtual Memory. Virtual Memory Issues. Virtual Memory Solutions. Locality of Reference. Virtual Memory with Segmentation. Page
More informationPage 1 of 5. IS 335: Information Technology in Business Lecture Outline Operating Systems
Lecture Outline Operating Systems Objectives Describe the functions and layers of an operating system List the resources allocated by the operating system and describe the allocation process Explain how
More informationCS 61C: Great Ideas in Computer Architecture Virtual Memory Cont.
CS 61C: Great Ideas in Computer Architecture Virtual Memory Cont. Instructors: Vladimir Stojanovic & Nicholas Weaver http://inst.eecs.berkeley.edu/~cs61c/ 1 Bare 5-Stage Pipeline Physical Address PC Inst.
More informationA3 Computer Architecture
A3 Computer Architecture Engineering Science 3rd year A3 Lectures Prof David Murray david.murray@eng.ox.ac.uk www.robots.ox.ac.uk/ dwm/courses/3co Michaelmas 2000 1 / 1 6. Stacks, Subroutines, and Memory
More informationSegmentation. 16.1 Segmentation: Generalized Base/Bounds
16 Segmentation So far we have been putting the entire address space of each process in memory. With the base and bounds registers, the OS can easily relocate processes to different parts of physical memory.
More informationOperating System Tutorial
Operating System Tutorial OPERATING SYSTEM TUTORIAL Simply Easy Learning by tutorialspoint.com tutorialspoint.com i ABOUT THE TUTORIAL Operating System Tutorial An operating system (OS) is a collection
More informationCOS 318: Operating Systems. Virtual Memory and Address Translation
COS 318: Operating Systems Virtual Memory and Address Translation Today s Topics Midterm Results Virtual Memory Virtualization Protection Address Translation Base and bound Segmentation Paging Translation
More informationHow To Write A Page Table
12 Paging: Introduction Remember our goal: to virtualize memory. Segmentation (a generalization of dynamic relocation) helped us do this, but has some problems; in particular, managing free space becomes
More informationOPERATING SYSTEM - VIRTUAL MEMORY
OPERATING SYSTEM - VIRTUAL MEMORY http://www.tutorialspoint.com/operating_system/os_virtual_memory.htm Copyright tutorialspoint.com A computer can address more memory than the amount physically installed
More informationChapter 2: OS Overview
Chapter 2: OS Overview CmSc 335 Operating Systems 1. Operating system objectives and functions Operating systems control and support the usage of computer systems. a. usage users of a computer system:
More informationLecture 17: Virtual Memory II. Goals of virtual memory
Lecture 17: Virtual Memory II Last Lecture: Introduction to virtual memory Today Review and continue virtual memory discussion Lecture 17 1 Goals of virtual memory Make it appear as if each process has:
More informationChapter 11: File System Implementation. Chapter 11: File System Implementation. Objectives. File-System Structure
Chapter 11: File System Implementation Chapter 11: File System Implementation File-System Structure File-System Implementation Directory Implementation Allocation Methods Free-Space Management Efficiency
More informationChapter 1 Computer System Overview
Operating Systems: Internals and Design Principles Chapter 1 Computer System Overview Eighth Edition By William Stallings Operating System Exploits the hardware resources of one or more processors Provides
More informationCHAPTER 17: File Management
CHAPTER 17: File Management The Architecture of Computer Hardware, Systems Software & Networking: An Information Technology Approach 4th Edition, Irv Englander John Wiley and Sons 2010 PowerPoint slides
More information361 Computer Architecture Lecture 14: Cache Memory
1 361 Computer Architecture Lecture 14 Memory cache.1 The Motivation for s Memory System Processor DRAM Motivation Large memories (DRAM) are slow Small memories (SRAM) are fast Make the average access
More informationVirtual Memory. Virtual Memory. Paging. CSE 380 Computer Operating Systems. Paging (1)
Virtual Memory CSE 380 Computer Operating Systems Instructor: Insup Lee University of Pennsylvania Fall 2003 Lecture Note: Virtual Memory (revised version) 1 Recall: memory allocation with variable partitions
More informationMemory management. Chapter 4: Memory Management. Memory hierarchy. In an ideal world. Basic memory management. Fixed partitions: multiple programs
Memory management Chater : Memory Management Part : Mechanisms for Managing Memory asic management Swaing Virtual Page relacement algorithms Modeling age relacement algorithms Design issues for aging systems
More informationDisk Space Management Methods
Volume 1, Issue 1, June 2013 International Journal of Advance Research in Computer Science and Management Studies Research Paper Available online at: www.ijarcsms.com Disk Space Management Methods Ramakrishna
More informationChapter 2 Basic Structure of Computers. Jin-Fu Li Department of Electrical Engineering National Central University Jungli, Taiwan
Chapter 2 Basic Structure of Computers Jin-Fu Li Department of Electrical Engineering National Central University Jungli, Taiwan Outline Functional Units Basic Operational Concepts Bus Structures Software
More informationPeter J. Denning, Naval Postgraduate School, Monterey, California
VIRTUAL MEMORY Peter J. Denning, Naval Postgraduate School, Monterey, California January 2008 Rev 6/5/08 Abstract: Virtual memory is the simulation of a storage space so large that users do not need to
More informationComputer Architecture
Computer Architecture Slide Sets WS 2013/2014 Prof. Dr. Uwe Brinkschulte M.Sc. Benjamin Betting Part 11 Memory Management Computer Architecture Part 11 page 1 of 44 Prof. Dr. Uwe Brinkschulte, M.Sc. Benjamin
More informationAdvanced Computer Architecture-CS501. Computer Systems Design and Architecture 2.1, 2.2, 3.2
Lecture Handout Computer Architecture Lecture No. 2 Reading Material Vincent P. Heuring&Harry F. Jordan Chapter 2,Chapter3 Computer Systems Design and Architecture 2.1, 2.2, 3.2 Summary 1) A taxonomy of
More informationStack Allocation. Run-Time Data Structures. Static Structures
Run-Time Data Structures Stack Allocation Static Structures For static structures, a fixed address is used throughout execution. This is the oldest and simplest memory organization. In current compilers,
More informationOutline: Operating Systems
Outline: Operating Systems What is an OS OS Functions Multitasking Virtual Memory File Systems Window systems PC Operating System Wars: Windows vs. Linux 1 Operating System provides a way to boot (start)
More informationHyperThreading Support in VMware ESX Server 2.1
HyperThreading Support in VMware ESX Server 2.1 Summary VMware ESX Server 2.1 now fully supports Intel s new Hyper-Threading Technology (HT). This paper explains the changes that an administrator can expect
More informationBoard Notes on Virtual Memory
Board Notes on Virtual Memory Part A: Why Virtual Memory? - Letʼs user program size exceed the size of the physical address space - Supports protection o Donʼt know which program might share memory at
More informationa storage location directly on the CPU, used for temporary storage of small amounts of data during processing.
CS143 Handout 18 Summer 2008 30 July, 2008 Processor Architectures Handout written by Maggie Johnson and revised by Julie Zelenski. Architecture Vocabulary Let s review a few relevant hardware definitions:
More informationLecture 10: Dynamic Memory Allocation 1: Into the jaws of malloc()
CS61: Systems Programming and Machine Organization Harvard University, Fall 2009 Lecture 10: Dynamic Memory Allocation 1: Into the jaws of malloc() Prof. Matt Welsh October 6, 2009 Topics for today Dynamic
More informationPhysical Data Organization
Physical Data Organization Database design using logical model of the database - appropriate level for users to focus on - user independence from implementation details Performance - other major factor
More informationComputers. Hardware. The Central Processing Unit (CPU) CMPT 125: Lecture 1: Understanding the Computer
Computers CMPT 125: Lecture 1: Understanding the Computer Tamara Smyth, tamaras@cs.sfu.ca School of Computing Science, Simon Fraser University January 3, 2009 A computer performs 2 basic functions: 1.
More informationChapter 12 File Management
Operating Systems: Internals and Design Principles, 6/E William Stallings Chapter 12 File Management Dave Bremer Otago Polytechnic, N.Z. 2008, Prentice Hall Roadmap Overview File organisation and Access
More informationChapter 11: File System Implementation. Operating System Concepts with Java 8 th Edition
Chapter 11: File System Implementation 11.1 Silberschatz, Galvin and Gagne 2009 Chapter 11: File System Implementation File-System Structure File-System Implementation Directory Implementation Allocation
More informationChapter 12 File Management. Roadmap
Operating Systems: Internals and Design Principles, 6/E William Stallings Chapter 12 File Management Dave Bremer Otago Polytechnic, N.Z. 2008, Prentice Hall Overview Roadmap File organisation and Access
More informationOperating Systems CSE 410, Spring 2004. File Management. Stephen Wagner Michigan State University
Operating Systems CSE 410, Spring 2004 File Management Stephen Wagner Michigan State University File Management File management system has traditionally been considered part of the operating system. Applications
More informationFile-System Implementation
File-System Implementation 11 CHAPTER In this chapter we discuss various methods for storing information on secondary storage. The basic issues are device directory, free space management, and space allocation
More informationConvenience: An OS makes a computer more convenient to use. Efficiency: An OS allows the computer system resources to be used in an efficient manner.
Introduction to Operating System PCSC-301 (For UG students) (Class notes and reference books are required to complete this study) Release Date: 27.12.2014 Operating System Objectives and Functions An OS
More informationx64 Servers: Do you want 64 or 32 bit apps with that server?
TMurgent Technologies x64 Servers: Do you want 64 or 32 bit apps with that server? White Paper by Tim Mangan TMurgent Technologies February, 2006 Introduction New servers based on what is generally called
More informationOperating System Overview. Otto J. Anshus
Operating System Overview Otto J. Anshus A Typical Computer CPU... CPU Memory Chipset I/O bus ROM Keyboard Network A Typical Computer System CPU. CPU Memory Application(s) Operating System ROM OS Apps
More information1 File Management. 1.1 Naming. COMP 242 Class Notes Section 6: File Management
COMP 242 Class Notes Section 6: File Management 1 File Management We shall now examine how an operating system provides file management. We shall define a file to be a collection of permanent data with
More informationRecord Storage and Primary File Organization
Record Storage and Primary File Organization 1 C H A P T E R 4 Contents Introduction Secondary Storage Devices Buffering of Blocks Placing File Records on Disk Operations on Files Files of Unordered Records
More informationFile System & Device Drive. Overview of Mass Storage Structure. Moving head Disk Mechanism. HDD Pictures 11/13/2014. CS341: Operating System
CS341: Operating System Lect 36: 1 st Nov 2014 Dr. A. Sahu Dept of Comp. Sc. & Engg. Indian Institute of Technology Guwahati File System & Device Drive Mass Storage Disk Structure Disk Arm Scheduling RAID
More information2) Write in detail the issues in the design of code generator.
COMPUTER SCIENCE AND ENGINEERING VI SEM CSE Principles of Compiler Design Unit-IV Question and answers UNIT IV CODE GENERATION 9 Issues in the design of code generator The target machine Runtime Storage
More informationPaging: Introduction. 18.1 A Simple Example And Overview
18 Paging: Introduction It is sometimes said that the operating system takes one of two approaches when solving most any space-management problem. The first approach is to chop things up into variable-sized
More informationHardware Assisted Virtualization
Hardware Assisted Virtualization G. Lettieri 21 Oct. 2015 1 Introduction In the hardware-assisted virtualization technique we try to execute the instructions of the target machine directly on the host
More informationKeil C51 Cross Compiler
Keil C51 Cross Compiler ANSI C Compiler Generates fast compact code for the 8051 and it s derivatives Advantages of C over Assembler Do not need to know the microcontroller instruction set Register allocation
More informationOn Demand Loading of Code in MMUless Embedded System
On Demand Loading of Code in MMUless Embedded System Sunil R Gandhi *. Chetan D Pachange, Jr.** Mandar R Vaidya***, Swapnilkumar S Khorate**** *Pune Institute of Computer Technology, Pune INDIA (Mob- 8600867094;
More informationSystem Virtual Machines
System Virtual Machines Introduction Key concepts Resource virtualization processors memory I/O devices Performance issues Applications 1 Introduction System virtual machine capable of supporting multiple
More information6. Storage and File Structures
ECS-165A WQ 11 110 6. Storage and File Structures Goals Understand the basic concepts underlying different storage media, buffer management, files structures, and organization of records in files. Contents
More informationIntroduction Disks RAID Tertiary storage. Mass Storage. CMSC 412, University of Maryland. Guest lecturer: David Hovemeyer.
Guest lecturer: David Hovemeyer November 15, 2004 The memory hierarchy Red = Level Access time Capacity Features Registers nanoseconds 100s of bytes fixed Cache nanoseconds 1-2 MB fixed RAM nanoseconds
More informationChapter 11 I/O Management and Disk Scheduling
Operating Systems: Internals and Design Principles, 6/E William Stallings Chapter 11 I/O Management and Disk Scheduling Dave Bremer Otago Polytechnic, NZ 2008, Prentice Hall I/O Devices Roadmap Organization
More informationLogical Operations. Control Unit. Contents. Arithmetic Operations. Objectives. The Central Processing Unit: Arithmetic / Logic Unit.
Objectives The Central Processing Unit: What Goes on Inside the Computer Chapter 4 Identify the components of the central processing unit and how they work together and interact with memory Describe how
More informationAn Introduction to Computer Science and Computer Organization Comp 150 Fall 2008
An Introduction to Computer Science and Computer Organization Comp 150 Fall 2008 Computer Science the study of algorithms, including Their formal and mathematical properties Their hardware realizations
More informationFull and Para Virtualization
Full and Para Virtualization Dr. Sanjay P. Ahuja, Ph.D. 2010-14 FIS Distinguished Professor of Computer Science School of Computing, UNF x86 Hardware Virtualization The x86 architecture offers four levels
More informationCS 464/564 Introduction to Database Management System Instructor: Abdullah Mueen
CS 464/564 Introduction to Database Management System Instructor: Abdullah Mueen LECTURE 14: DATA STORAGE AND REPRESENTATION Data Storage Memory Hierarchy Disks Fields, Records, Blocks Variable-length
More informationOrganization of Programming Languages CS320/520N. Lecture 05. Razvan C. Bunescu School of Electrical Engineering and Computer Science bunescu@ohio.
Organization of Programming Languages CS320/520N Razvan C. Bunescu School of Electrical Engineering and Computer Science bunescu@ohio.edu Names, Bindings, and Scopes A name is a symbolic identifier used
More informationOS OBJECTIVE QUESTIONS
OS OBJECTIVE QUESTIONS Which one of the following is Little s formula Where n is the average queue length, W is the time that a process waits 1)n=Lambda*W 2)n=Lambda/W 3)n=Lambda^W 4)n=Lambda*(W-n) Answer:1
More informationChapter 12 File Management
Operating Systems: Internals and Design Principles Chapter 12 File Management Eighth Edition By William Stallings Files Data collections created by users The File System is one of the most important parts
More informationCS 377: Operating Systems. Outline. A review of what you ve learned, and how it applies to a real operating system. Lecture 25 - Linux Case Study
CS 377: Operating Systems Lecture 25 - Linux Case Study Guest Lecturer: Tim Wood Outline Linux History Design Principles System Overview Process Scheduling Memory Management File Systems A review of what
More informationThis tutorial will take you through step by step approach while learning Operating System concepts.
About the Tutorial An operating system (OS) is a collection of software that manages computer hardware resources and provides common services for computer programs. The operating system is a vital component
More informationPOSIX. RTOSes Part I. POSIX Versions. POSIX Versions (2)
RTOSes Part I Christopher Kenna September 24, 2010 POSIX Portable Operating System for UnIX Application portability at source-code level POSIX Family formally known as IEEE 1003 Originally 17 separate
More informationReconfigurable Architecture Requirements for Co-Designed Virtual Machines
Reconfigurable Architecture Requirements for Co-Designed Virtual Machines Kenneth B. Kent University of New Brunswick Faculty of Computer Science Fredericton, New Brunswick, Canada ken@unb.ca Micaela Serra
More informationINTRODUCTION The collection of data that makes up a computerized database must be stored physically on some computer storage medium.
Chapter 4: Record Storage and Primary File Organization 1 Record Storage and Primary File Organization INTRODUCTION The collection of data that makes up a computerized database must be stored physically
More informationChapter 3: Operating-System Structures. System Components Operating System Services System Calls System Programs System Structure Virtual Machines
Chapter 3: Operating-System Structures System Components Operating System Services System Calls System Programs System Structure Virtual Machines Operating System Concepts 3.1 Common System Components
More informationFile System Management
Lecture 7: Storage Management File System Management Contents Non volatile memory Tape, HDD, SSD Files & File System Interface Directories & their Organization File System Implementation Disk Space Allocation
More informationPart III Storage Management. Chapter 11: File System Implementation
Part III Storage Management Chapter 11: File System Implementation 1 Layered File System 2 Overview: 1/4 A file system has on-disk and in-memory information. A disk may contain the following for implementing
More informationChapter 5 Cloud Resource Virtualization
Chapter 5 Cloud Resource Virtualization Contents Virtualization. Layering and virtualization. Virtual machine monitor. Virtual machine. Performance and security isolation. Architectural support for virtualization.
More informationChapter 11: File System Implementation. Operating System Concepts 8 th Edition
Chapter 11: File System Implementation Operating System Concepts 8 th Edition Silberschatz, Galvin and Gagne 2009 Chapter 11: File System Implementation File-System Structure File-System Implementation
More information1/20/2016 INTRODUCTION
INTRODUCTION 1 Programming languages have common concepts that are seen in all languages This course will discuss and illustrate these common concepts: Syntax Names Types Semantics Memory Management We
More informationKernel Optimizations for KVM. Rik van Riel Senior Software Engineer, Red Hat June 25 2010
Kernel Optimizations for KVM Rik van Riel Senior Software Engineer, Red Hat June 25 2010 Kernel Optimizations for KVM What is virtualization performance? Benefits of developing both guest and host KVM
More information1 Organization of Operating Systems
COMP 730 (242) Class Notes Section 10: Organization of Operating Systems 1 Organization of Operating Systems We have studied in detail the organization of Xinu. Naturally, this organization is far from
More informationW4118 Operating Systems. Instructor: Junfeng Yang
W4118 Operating Systems Instructor: Junfeng Yang Outline x86 segmentation and paging hardware Linux address space translation Copy-on-write Linux page replacement algorithm Linux dynamic memory allocation
More informationSymbol Tables. Introduction
Symbol Tables Introduction A compiler needs to collect and use information about the names appearing in the source program. This information is entered into a data structure called a symbol table. The
More informationUnit 4.3 - Storage Structures 1. Storage Structures. Unit 4.3
Storage Structures Unit 4.3 Unit 4.3 - Storage Structures 1 The Physical Store Storage Capacity Medium Transfer Rate Seek Time Main Memory 800 MB/s 500 MB Instant Hard Drive 10 MB/s 120 GB 10 ms CD-ROM
More informationVirtual Memory. How is it possible for each process to have contiguous addresses and so many of them? A System Using Virtual Addressing
How is it possible for each process to have contiguous addresses and so many of them? Computer Systems Organization (Spring ) CSCI-UA, Section Instructor: Joanna Klukowska Teaching Assistants: Paige Connelly
More informationChapter 14 MS-DOS Operating System
Understanding Operating Systems, Fifth Edition 14-1 Chapter 14 MS-DOS Operating System At a Glance Instructor s Manual Table of Contents Overview Objectives s Quick Quizzes Class Discussion Topics Additional
More informationAPP INVENTOR. Test Review
APP INVENTOR Test Review Main Concepts App Inventor Lists Creating Random Numbers Variables Searching and Sorting Data Linear Search Binary Search Selection Sort Quick Sort Abstraction Modulus Division
More informationChapter 3 Operating-System Structures
Contents 1. Introduction 2. Computer-System Structures 3. Operating-System Structures 4. Processes 5. Threads 6. CPU Scheduling 7. Process Synchronization 8. Deadlocks 9. Memory Management 10. Virtual
More informationTraditional IBM Mainframe Operating Principles
C H A P T E R 1 7 Traditional IBM Mainframe Operating Principles WHEN YOU FINISH READING THIS CHAPTER YOU SHOULD BE ABLE TO: Distinguish between an absolute address and a relative address. Briefly explain
More informationMore on Pipelining and Pipelines in Real Machines CS 333 Fall 2006 Main Ideas Data Hazards RAW WAR WAW More pipeline stall reduction techniques Branch prediction» static» dynamic bimodal branch prediction
More informationThe Classical Architecture. Storage 1 / 36
1 / 36 The Problem Application Data? Filesystem Logical Drive Physical Drive 2 / 36 Requirements There are different classes of requirements: Data Independence application is shielded from physical storage
More information